Calibration should be done once prior first flight of the day and if you have multiple batterys you can replace them and fly anafi without calibrating again....calibrating before every flight is habit from bebop 2 ,we found out that almost every time someone had flyaway calibration was not done prior the flight,reason most of parrot pilots calibrate bebop before every flight and i must say that after that we had less flyaways...anafi being “parrot “product is a good reason why i calibrate before every flight